High speed angle handpiece



Feb. 26, 1963 E. HoFFMl-:lsTER ETAL 3,078,576

HIGH SPEED ANGLE HANDPIECE Filed NOV. 28, 1958 4 Sheets-Sheet 1 Feb- 26,1963 E. HoFFMElsTER ETAL 3,078,576

HIGH SPEED ANGLE HANDPIECE Filed NOV. 28, 1958 4 Sheets-Sheet 2 .3jr gh,Y

Feb. 26, 1963 E. HoFFMElsTER ETAL 3,078,576

HIGH SPEED ANGLE HANDPIECE 4 Sheets-Sheet` 3 Filed Nov. 28, 1958 E.HoFFMl-:xsTl-:R ETAL 3,078,576

HIGH SPEED ANGLE HANDPIECE Feb. 26,1963

4 Sheets-Sheet 4 Filed Nov. 28. 1958 Me/'ef By, ,i, QM

3,078,576 HEGH SPEED ANGLE HANDPIECE Erich Hottmeister and Kurt Rohm,Biberach (Riss), Germany, assignors to Alois Kaltenhnch and ErichHonrneister, the responsible partners of Kaitenbach & Voigt, akommanditgeseilschait, Biberach (Riss), Germany Filed Nov. 28, 95, Ser.No. 777,132 `Claims priority, application Germany Nov. 30, 1957 9Claims. (Cl. Sil-27) The invention relates to ahigh-speed anglehandpiece, with shank elbow if appropriate, for dental purposes, havinga turbine which is driven by compressed air and is arranged in the anglehandpiece head, the supply and, at least partly, also the discharge ofthe compressed air and the supply of Water to the forward end of thehead being effected through the interior of the instrument, and areleasable coupling for the water and air supply pipes being arranged atthe rear end of the instrument.

It has already been proposed for such instruments to be made in onepiece, undivided, from the head down to the coupling at the rear end ofthe instrument. This construction of the instrument affords considerablediiculties as regards cleaning the instrument, especially if the anglehandpieces are constructed with an elbow in the shank.

In order to avoid these diii'iculties, according to a further proposalthe instrument has been divided transversely at some distance from thehead, and at the place of division and also at the rear end of theinstrument packing means are arranged for the sub-divided water and airpipes.y But this solution has the disadvantage that a complete secondcoupling has to be provided at the place where the instrument is dividedtransversely, and this makes the manufacture of the instrument moreexpensive.

According to the invention, it is proposed for the instrument sleeve tobe divided transversely at the front and rear ends of the actual handletube, to arrange for the water and air supply pipes to extend without abreak from the head to the coupling at the rear end of the instrumentand to make the part of the instrument sleeve adjoining the handle tubecapable of being connected to a supporting sleeve for the pipes.

According to the invention it is further proposed that the connection ofthe sleeve adjoining the handle tube, to the supporting sleeve for thepipes, shall serve at the same time to provide for the centering andsecuring of the handle tube.

In this way, the instrument can easily be taken to pieces for cleaningpurposes without any need for a second coupling for the water and airsupply pipes, and also if the turbine in the angle handpiece headbecomes defective, the entire head with the adjoining sleeve and waterand air supply pipes extending through and within the instrument can bereplaced. This replacement can easily be carried out by the dentist, andit should be noted that the manufacturing costs for the head with theadjoining sleeve and adjoining pipes are inconsiderable relatively tothe cost of the turbine situated in the head.

The supporting sleeve for the pipes can, according to the invention, bearranged at the front end of the sleeve adjoining the handle tube. Inthis case the forward in- 'fine ternally threaded end of the sleeveadjoining the handle tube is screwed on to the pipe supporting sleeve,which is externally threaded.

The front end of the possibly bent handle tube is preferably providedwith an internal cone into which a corresponding external cone on therear end of the head sleeve engages when the individual sleeves areassembled together.

It is particularly expedient to insert the pipe supporting sleeve in therear end of the shank elbow or for it to be constituted thereby, and toprovide the sleeve adjoining the handle tube with a tubular extensionwhich extends through the entire handle tube and whose front end isadapted to be connected to the shank elbow.

In this Way, the result is achieved that the pipes extend from the shankelbow through the entire instrument sleeve completely free down to thecoupling arranged on the rear end of the instrument, so that vibrationsof the pipes, which cannot be Wholly avoided owing to the very highrotational speed of the turbine situated in the head of the instrument,are not transmitted to the instrument sleeve and more particularly thehandle sleeve.

In this construction of angle handpiece, it isalso proposed that thehead sleeve, handle tube andadjoining sleeve be fixed relatively to oneanother by a locking nut which is adapted to be screwed, between therear end of the handle tube and the front end of the sleeve adjoiningthe handle tube, on a screwthread of the tubular extension of thesleeve. In this way, the above-mentioned sleeves can be clamped togetherand taken apart very simply merely by rotating the locking nut.

Expediently, a further pipe supporting sleeve is arranged, with adequateclearance therefrom, within the front end of the sleeve adjoining thehandle tube, in order in this way to tix the pipes also relatively toone another in the middle part of the instrument sleeve, withouteffecting a direct connection to the instrument sleeve.

It is also proposed to mount on the rear end of the head sleeve anexternally conical sleeve of flexible material, eg. a synthetic plasticmaterial or rubber, whose outer cone, when the head sleeve and handletube are assembled together, engages in a corresponding internal cone ofthe iront end of the handle tube. In this way, the vibrations producedin the angle handpiece head relatively to the handle tube when theturbine is operating, are damped to a very considerable extent.

For a better understanding of the invention and to show how it may becarried intoy eiect, the same will now be described, by way of example,with reference to the accompanying drawings, in which;

FIGURE l is a longitudinal sectional view of one form of embodiment ofhigh-speed angle handpiece with shank elbow,

FIGURE 2 is a side view of the angle handpiece head with the adjoiningIsleeve `and the water and air supply pipes,

FIGURE 3 is a longitudinal sectional view of the handle tube,

FIGURE 4 is a longitudinal sectional view of the sleeve adjoining thehandle tube at the rear thereof,

FIGURE 5 is a cross-section through the supporting sleeve for the waterand air supply pipes taken on the line V-V of FIGURE 2,

FIGURE 6 is a longitudinal sectional view of the cup sleeve forming acomponent of the coupling which is situated at the rear end of theinstrument,

FIGURE 7 is a front end view of the cup sleeve according to FIGURE 6,

FIGURE 8 is a longitudinal sectional view of the angle handpiece withshank elbow, with the handpiece head and adjoining head sleeve shown inside view,

FIGURE 9 is a longitudinal sectional view ofthe angle handpiece headwith adjoining head sleeve and shank elbow with the pipes for the supplyof water and 'air shownin side view, p Y

FIGURE l is a section taken on the line X--X of FIGURE 9, y t

FIGURE l1 is a section taken on the line XI-XI of FIGURE9,

l FIGURE 12 isa section taken on the line XII-XII of FIGURE 9,

FIGURE 13 is a. longitudinal sectional view of the actual handle tube. lf FIGURE l4'is a longitudinal sectional view of the rear part of theinstrument sleeve, v l

` FIGURE `15 is a longitudinal sectional view of the lockins hut. v

FIGURE 16 isa longitudinal sectional view of the cup sleeve forming partof the coupling situated at the `rear end of the instrument, 'andyFIGURE 17 is a f ront end view of the cup sleeve acordig toFIGURE 16. v

In the form of embodiment according'to FIGURES 1 to 1,1 is an anglehandpiece head in which is arranged 'an air-driven turbine. Connected tothe head is a head sleeve 2 which at its rear end is formed with anexternal cone 3. Anair supply pipe 4 and a waterA supply pipe 5rearwardly out of the head. The two ends ot these pipes are xed in aninsert element 27 provided in `head sleeve 2, this element itself beingvconnected fast to the head sleeve. From the front end of the air supplypipe 4, therair is supplied through a bore 28 in the insert element 27to the turbine arranged in the head of the angle handpiece. Into the endof the water supply pipe 5 there opens a small pipe 29 which extendsobliqu'el'y tothe turbine axis and through which the water is suppliedt'o the tool (not shown) whose shank (also Vnot shown) is adapted to bemounted in the hollow shaft of the turbine. Inserted Vin the head sleevefollowing the insert element 27, is a further insert element 30 whichextends ds far as the bent-over forward e'nd ofthe handle sleeve and hasthe object of guiding the pipes 4 and 5 as far as this point. The rearends of the pipes 4 and 5 open into a coupling which is arranged at'therear end of the instrument, and the construction of which will bedescribed further hereinafter. The 'supply 'of compressed'air foroperating the airdr'iven turbine. in the angle handpiece head iseffected through the stub pipe 6 at the rear end of the instrument, a,compressed air supply hose (not shown) being tted over the free end ofthe said stub pipe. The compressed air supply hose is clamped on thestub pipe 6 by means 'of a locking nut 7 which is screwed on to athickened rear end portion of the stub pipe 6. A thickened front endportion of the stubpipe 6 is formed with a relatively wide bore 8Y whichmerges into the interior of the stub pipe 6A, and with a relativelynarrow bore 9 in which a small pipe 10 is welded. The small pipe 10 isso bent that the free end is arranged axially in the stub pipe 6 andprojects slightly out of the latter. Mounted on the end of the pipe 10is a hose which extends through the interior of the compressed airsupply hose. Water is supplied through the hose which is arranged in theinterior of the compressed supply hose and which is mounted on the freeend of the small pipe 10. The compressed air pipe 4Vengageswith slightclearance in the -bore 8 of the stub pipe, whereas the water pipe 5engages with some clearance in the relatively smallb'ore 9..

Engaging over the thickened front end of the stub pipe 6, is a cupsleeve 11 having a bottom end portion 12 formed with apertures throughwhich the pipes 4 and 5 extend. At the rear end, the cup sleeve isprovided with an outwardly projecting flange 13. Arranged between thebottom 12 of the cup sleeve 11 and the rear thickened end part of thestub pipe 6 is a packing disc 14 which is also formed with aperturesthrough which the pipes 4 and 5 extend. Upon tightening of the lockingnut 15, which screws on to the rear end of the sleeve 16, an outwardlyprojecting ange 17 of the stub pipe 6 is pressed against the ange 13 ofthe cup sleeve 11 and this flange is pressed against the rear end faceof the sleeve 16, at the same time compressing the packing disc 14, thussealing the pipes 4 and 5 in the bores 8 and 9.

The pipes 4 and 5 are supported at the rear end of the handle tube 18 bya supporting sleeve 19. The sup porting sleeve 19 is provided withexternal screwthreading 20 on which is screwed the internalscrewthreading 21 on the front end of the sleeve 16. The rear end of thehandle tube 18 bears against the collar 22 at the front end of thesleeve 16, lthus centering the said handle tube at the same timerelatively to the sleeve 16. v The handle tube 18 is provided at itsfront end with an attached elbow piece 23 which is formed with aninternal cone 24 towards its free end. Upon assembly of the head'sleeve2, handle tube 1,8 and sleeve 16 which adjoi'ns the rear of the handletube, the outer cone 3 on the rear end of the head sleeve 2 is drawninto the inner cone 24 of the shank elbow 23 of the handle tube 18, sothat the head Vsleeve and the handle tube are thereby also centeredrelatively to. one another.

Discharge of the compressed air used for driving the turbine takes placein known manner partly through the front and rear faces of the anglehandpiece head 1 and partly rearwardly through the instrument. Thisportion of the discharge air issues from the rear end of the headsleeve, then ows through the handle tube 18, aperture 25 in thesupporting sleeve 19, then through the sleeve 16, and finally passes outinto the open air between lateral tlat portions 26 of the cup sleeve 11and the inner wall of the sleeve V16. A A p In therorm of embodimentaccording to FIGURES S to 17', 31 is the angle handpiece head and 32 thehead ,sleeve adjoining the angle handpiece head.

As can be seen from FIGURE 9, there is arranged in known manner withinthe angle handpiece head 31 a turbine which is driven by compressed airand which consists 'or the rotor 33 and turbine Vhousing 34. The rotor33 is mounted in ball bearings 35 at the front and rear ends of therotor shaft. Arranged within the hollow rotor shaft is a clamping sleeve36 which is used for receiving the drill shank. Ihe clamping sleeve 36can consist of a exible synthetic plastic material sleeve or an elasticmetal sleeve. Fixed in the upper end of the head sleeve 32 adjoining theangle handpiece head 31 is an insert element 37 formed with a bore 38which accommodates the front end of an air supply pipe 39. The insertelement 37 also has a bore 40 through which air is supplied to theturbine blades of the rotor 33. Inserted in a further bore 41 of 1 theinsert element 37 is the end of a Water supply pipe 42.

The water is supplied fromv the end of the supply pipe 42 through thesmall pipe 43 extending obliquely relatively to the axis of the headsleeve, out of the front head end on to the tool whose shank (not shownin the drawings) is inserted in the clamping sleeve 36 of the anglehandpiece head.

, The pipes 39 and 42 inserted fast in the insert element 37 extendthrough the shank elbow 44 undivided as far as the rear end of theinstrument. A supporting sleeve 45V (FIGURE 1l) for the pipes 38 and 42is inserted fast in the rear end of the shank elbow 44. The supportingsleeve 4 5 for the pipes 39 and 42 is also formed with an aperture'46through which part of the turbine discharge air is guided to the rearend of the instrument. The

turbine discharge air passes partly by way of the ball bearings 35through holes in the front and rear ends of the head towards theoutside. Partly it is discharged rearwardly through the longitudinalgroove 47 in the insert element 37 within the head sleeve 32 and theshank elbow 44 through the aperture 46 of the supporting sleeve towardsthe rear.

The head sleeve 32 is followed by the actual instrument sleeve. Theinstrument sleeve consists ofthe handle tube proper `48 (FIGURE 13) andthe sleeve 49 which adjoins the handle sleeve rearwardly thereof (FIGURE14). The forward bent-over end 5) of the handle sleeve is formed with aninternal cone 51 which, after the instrument is assembled, sits on theouter cone 52a of the sleeve S2 which is arranged on the rear end of thehead sleeve 32 and which is made of a exible material, e.g. a syntheticplastic material or rubber. The sleeve 49 adjoining the handle tubecomprises at its front end a tubular extension 53 which extends withslight clearance through the interior of the handle tube 48. The frontend of the tubular extension 53 is formed with an internal screwthread54 which can be screwed on to the external screwthread 55 on the rearpart of the shank elbow 44. Arranged between the rear end of the handletube 453 and the front end of the sleeve 49 adjoining the handle tube isa clamping nut 56 which can be screwed on to the screwthread 57 on therear end of the tubular extension 53.

The manner of assembling the component parts of the instrument is thatfirst of all the clamping nut 56 mounted on the screwthread 57 of thetubular extension 53 is screwed rearwardly until abutment against thesleeve 49 is achieved. Then the handle tube 48 is fitted over thetubular extension 53 of the sleeve 49, and then these two parts arefitted over the pipes 39 and 42 which project rearwardly out of theshank elbow, and the forward end of the tubular extension 53 is screwedon to the screwthread 55 on the rear part of the shank elbow 44.

The head sleeve, handle tube and adjoining sleeve are then xedrelatively to one another in that the locking nut 56 is screwedforwardly by means of a key whose end is inserted in a radial hole 5S inthe locking nut, whereby the external cone 52 on the rear end of thehead sleeve 32 becomes connected fast to the internal cone 51 of thefront bent-over end 5t) of the handle tube, and the rear end of thehandle tube 48 at the same time abuts securely on the front end face ofthe locking nut 56.

Arranged within the front end of the sleeve 49, with adequate clearancewith respect to the sleeve 49, is a further supporting sleeve 59 for thepipes 39 and 42, whereby the two parts are held in a xed arrangementrelatively to one another (FIGURE 12).

As in the form of embodiment according to FIGURES 1 to 7, the compressedair for working the air turbine in the angle handpiece head is suppliedfrom the rear end of the instrument through the stub pipe 66 over whosefree end is iitted the compressed air supply hose, which is not shown inthe drawings. The compressed air hose is clamped fast on the stub pipe69 by the locking nut 72 which is screwed on to the thickened rear endof the stub pipe 6d. The thickened front end of the stub pipe 60 has arelatively wide bore 62 which merges into the interior of the stub pipe60, and a relatively narrow bore 63 in which is inserted the small pipe64. The small pipe 64 is so bent that the free end is arranged axiallyin the stub pipe 66* and projects slightly out of the latter. Mounted onthe free end is a hose which extends through the interior of the hoseused for the supply of compressed air. Water is supplied through thehose which is arranged in the interior of the compressed air supply hoseand which is mounted on the free end of the small pipe 64. Thecompressed air pipe 39 engages with slight clearance in the bore 62 ofthe stub pipe 60, whereas the small water pipe 42 engages with someclearance in' the relatively small bore 63.

Engaging over the thickened front end of the stub pipe 60 is a cupsleeve 65 (FIGURE 16), which in its bottom portion 66 is formed withapertures 67, 68 through which the pipes 39 and 42 extend. At the rearend, the cup sleeve is provided with an outwardly projecting flange 69.Arranged between the bottom 66 of the cup sleeve 65 and the rearthickened end of the stub pipe 60 is a packing disc 76 which is alsoformed with apertures through which the pipes 39 and 42 extend. Upontightening of the locking nut 61 which screws on to the rear end of thesleeve 49, the outwardly projecting flange 69 of the stub pipe 69 ispressed against the ange 69 of the cup sleeve 65 and this flange ispressed against the rear end face of the sleeve 49, simultaneouslycompressing the packing disc 76, thus sealing the pipes 39 and 42 in theapertures 62 and 63. In order that the cup sleeve cannot rotate when thelocking nut is being tightened, the ange 69 of the cup sleeve isprovided in the direction of the adjoining instrument sleeve 49 with atootning 73 which engages in a corresponding toothing '74 in the rearend face of the sleeve 49.

The discharge air from the turbine, which passes through the head sleeveand the aperture 46 in the supporting sleeve 45 into the interior of theinstrument sleeve, flows between the lateral flattened portions 71 ofthe cup sleeve 65 and the inner wall of the sleeve 49 out into the openair.

We claim:

1. In a high speed air-driven dental drill of the character wherein acontra-angle handpiece is provided with a turbine housing at one end andwith means at the other end to supply motive air and water, thecombination including, a head sleeve ixed to a turbine housing, secondand third sleeves separably joined with each other and with said headsleeve in axially abutting relationship, conduit means for motive airand water iixed to said head sleeve and extending interiorly of thesecond and third sleeves for separable connection with a supply ofmotive air and Water, centering means for the conduit means positionedwithin one of said sleeves, coupling means connected with one of saidsleeves and separably connecting one end of one of the sleeves insealing engagenient with said conduit means, and locking means connectedwith one of said sleeves and detachably joining said three sleevestogether.

2. The invention as defined in claim l, wherein said second sleeve isaxially positioned between the head sleeve and the third sleeve, andsaid locking means is tixed to said conduit means, said locking meansbeing engageable with said third sleeve to urge said three sleeves intosaid axially abutting relationship.

3. The invention as defined in claim 1, wherein said centering means ispositioned adjacent the front end of the third sleeve.

4. The invention as .defined in claim 1, Iwherein said centering meanscomprises a cylindrical element, the exterior surface thereof beingthreaded, said centering means being fixed to said conduit means, saidthird sleeve being internally threaded for engagement with the threadsof the centering means.

5. The invention as dened in claim 1, wherein said head sleeve isprovided with a conically shaped end portion and said second sleeve isprovided with a conically shaped socket for detachable engagement withthe conically shaped end of the head sleeve.

6. The invention as defined in claim 5, wherein a conically shaped layerof resilient material is disposed between the conically shaped endportion of the head sleeve and the socket of the second sleeve.

7. The invention as defined in claim 1, wherein the end of said headsleeve is provided with a cylindrical axially extending elbow portion,said centering means being positioned in engagement with said elbow,said third sleeve 3,078,576 7 being provided with a. tubular extensionat one end extending through said second sleeve for detachableengagement with said elbow portion.

8. The invention as dened in claim 7, wherein said elbow portion andsaid third sleeve are provided with 5 inter-engaging threads, and saidtubular extension of the third sleeve is Vexterioriy threaded to receivea locking nut, said locking nut being operative to abut one end of1,7741733 the second sleeve for tightening the entire assembly. 210985179. The invention as defined in claim 7, wherein said 10 2,928,174

conduit means comprises at least two longitudinally extending pipes, andspacer means to transversely position said pipes with respect to eachother.

References Cited in the le of this patent UNITED STATES PATENTS StarckSept. 2, 1930 Staunt Nov. 9, 1937 White Mar. 15, 1960

1. IN A HIGH SPEED AIR-DRIVEN DENTAL DRILL OF THE CHARACTER WHEREIN ACONTRA-ANGLE HANDPIECE IS PROVIDED WITH A TURBINE HOUSING AT ONE END ANDWITH MEANS AT THE OTHER END TO SUPPLY MOTIVE AIR AND WATER, THECOMBINATION INCLUDING, A HEAD SLEEVE FIXED TO A TURBINE HOUSING, SECONDAND THIRD SLEEVES SEPARABLY JOINED WITH EACH OTHER AND WITH SAID HEADSLEEVE IN AXIALLY ABUTTING RELATIONSHIP, CONDUIT MEANS FOR MOTIVE AIRAND WATER FIXED TO SAID HEAD SLEEVE AND EXTENDING INTERIORLY OF THESECOND AND THIRD SLEEVE FOR SEPARABLE CONNECTION WITH A SUPPLY OF MOTIVEAIR AND WATER, CENTERING MEANS FOR THE CONDUIT MEAN POSITIONED WITHINONE OF SAID SLEEVES, COUPLING MEANS CONNECTED WITH ONE OF SAID SLEEVESAND SEPARABLY CONNECTING ONE END OF ONE OF THE SLEEVES IN SEALINGENGAGEMENT WITH SAID CONDUIT MEANS, AND LOCKING MEANS CONNECTED WITH ONEOF SAID SLEEVES AND DETACHABLY JOINING SAID THREE SLEEVES TOGETHER.